Brother LH4-B800E Service Manual page 102

4-13-5. Adjusting the cutting depth of the upper thread scissors
Cam
e
1. Turn off the power (with the feed mechanism at the home position), and then slowly move the trimmer driving arm
q forward until the driving arm roller e is at its highest position on the cam of the upper thread trimmer lever w.
2. Loosen the screw r, and then adjust the driving arm roller e so that the clearance between the stopper y of the
upper thread trimmer assembly t and the opening cam bracket u is 0—0.5 mm.
If the stopper y is adjusted so that it presses too firmly, it may cause the presser foot lifter pulse motor to go out
*
of step.
q
q
w
r
e
t
Clearance 0--0.5 mm
LH4-B800E
4. Adjustment
u
y
4 - 15